Recyclable laminated polyolefin-based film structures

ABSTRACT

A recyclable, laminated polyolefin-based film structure comprises two or more film plies laminated to each other. Each of the laminated film plies comprises one or more polyolefin-based films. The film structure has an energy-cured coating layer disposed on the outermost outward facing surface of the film structure and a printed ink layer on an interior surface of one of the polyolefin-based polyolefin layers. In certain embodiments, the outermost surface of the laminated polyolefin-based film structure has a melting temperature which is at least 100 degrees Celsius, and more preferably 180 degrees Celsius, higher than a melting temperature of the innermost surface of the laminated polyolefin-based film structure.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. nonprovisional applicationSer. No. 17/332,658 filed May 27, 2021, which, in turn, claims thepriority benefit of U.S. provisional application No. 63/030,612 filedMay 27, 2020. Each of the aforementioned applications is incorporatedherein by reference in its entirety.

BACKGROUND

The present disclosure relates to laminated polyolefin-based filmstructures, and more particularly, to laminated polyolefin-based filmstructures comprising two or more polyolefin-based film ply layerslaminated to each other. Each of the laminated films comprises one ormore polyolefin-based film layers. The film structure has anenergy-cured coating layer disposed on the outermost outward facingsurface of the film structure and a printed ink layer on an interiorsurface of one of the polyolefin-based film layers. The film structuresin accordance with this disclosure may advantageously be adapted toprovide a recyclable polyolefin-based film structure for flexible filmpackaging. In certain embodiments, the film structures herein arepolyethylene-based film structures. In certain embodiments, the filmstructures herein are polypropylene-based film structures.

The film structures disclosed herein may advantageously be used asflexible packaging films that are formed into packages, e.g. pouches,bags, overwraps, and the like, that protect consumable products fromspoiling or prematurely degrading in various environments throughout thedistribution and point of sale channels. Such packaging structures maybe used for packaging of food items, liquids, chemicals, health andbeauty products, pharmaceutical products, or other consumable productthat needs to be protected from oxygen and moisture throughout thedistribution channel environment.

Recyclable polyolefin-based films, such as polyethylene-based films andpolypropylene-based films, are far less resistant to mechanical andenergy forces when run on a packaging filling line due to the tensionsand heating bars. Previous attempts to run these materials have been metwith inferior quality packages, such as ink pick off or deforming. Thepresent development overcomes this limitation by providing a recyclablefilm that is heat resistant with a trapped ink system. This results inthe production of a package that is not deformed and lacks other defectssuch as ink pick off and scuffing.

Films having surface printed inks are vulnerable to the ink pick off andrubbing in more extreme environments, even where an energy-curedcoating, or other coating, is applied over the surface printed inks onthe same side of the web.

Films having reverse printed inks disposed between two polyolefin filmwebs without a coating or having and having a wet-based, ambient, orheated air-dried coating are generally known. However, such films lack asufficient degree of heat resistance to protect the integrity of the inklayer as well as the overall package structure from the heat associatedwith package forming and filling equipment, such as hot sealing bars.

The present disclosure provides an improved film structure thatovercomes the above-referenced problems and others.

SUMMARY

In one aspect, a laminated polyolefin-based film structure comprises afirst film ply comprising a first layer formed of a polyolefin-basedfilm containing at least 90% by weight polyolefin homopolymers,copolymers, or terpolymers and less than 10% by weight other polymercompositions. The first layer has a first surface and a second surfaceopposite the first surface. A second layer is disposed on the firstsurface of the first layer. The second layer comprises an energy-curedcoating and defines an outermost surface of the laminatedpolyolefin-based film structure. A second film ply comprises a thirdlayer formed of a polyolefin-based film containing at least 90% byweight polyolefin homopolymers, copolymers, or terpolymers and less than10% by weight other polymer compositions, the third layer having a firstsurface and a second surface opposite the first surface, the secondsurface of the third layer defining an innermost surface of thelaminated polyolefin-based film structure. An adhesive layer isinterposed between the first film ply and the second film ply andlaminates the first film ply to the second film ply. The first surfaceof the third layer faces the second surface of the first layer and aprinted layer is disposed intermediate the first layer and the thirdlayer.

In a more limited aspect, a melting temperature of the outermost surfaceof the laminated polyolefin-based film structure is at least 100 degreesCelsius higher than a melting temperature of the innermost surface ofthe laminated polyolefin-based film structure.

In another more limited aspect, the melting temperature of the outermostsurface of the laminated polyolefin-based film structure is at least 180degrees Celsius higher than a melting temperature of the innermostsurface of the laminated polyolefin-based film structure.

In another more limited aspect, the first layer and third layer areformed of a material selected from the group consisting ofpolyethylene-based films which contain at least 90% by weightpolyethylene homopolymers, copolymers, or terpolymers and less than 10%by weight other polymer compositions, polypropylene-based films whichcontains at least 90% by weight polypropylene homopolymers, copolymers,or terpolymers and less than 10% by weight other polymer compositions,and combinations thereof.

In another more limited aspect, the first layer is formed of apolyethylene-based film which contains at least 90% by weightpolyethylene homopolymers, copolymers, or terpolymers and less than 10%by weight other polymer compositions and the third layer is formed of apolyethylene-based film which contains at least 90% by weightpolyethylene homopolymers, copolymers, or terpolymers and less than 10%by weight other polymer compositions.

In another more limited aspect, the first layer is formed of apolyethylene-based films which contain at least 95% by weightpolyethylene homopolymers, copolymers, or terpolymers and less than 5%by weight other polymer compositions and the third layer is formed of apolyethylene-based film which contains at least 95% by weightpolyethylene homopolymers, copolymers, or terpolymers and less than 5%by weight other polymer compositions.

In another more limited aspect, the printed layer comprises a reverseprinted ink layer disposed on the second surface of the first layer.

In another more limited aspect, the printed layer comprises a forwardprinted ink layer disposed on the first surface of the third layer.

In another more limited aspect, the polyolefin-based film of the firstlayer and the polyolefin-based film of the third layer compriserecyclable polyolefin polymers.

In another aspect, a laminated polyolefin-based film structure comprisesa first film ply comprising a first layer formed of a polyolefin-basedfilm containing at least 90% by weight polyolefin homopolymers,copolymers, or terpolymers and less than 10% by weight other polymercompositions. The first layer has a first surface and a second surfaceopposite the first surface. A second layer is disposed on the firstsurface of the first layer, the second layer comprising an energy-curedcoating. A second film ply comprises a third layer formed of apolyolefin-based film containing at least 90% by weight polyolefinhomopolymers, copolymers, or terpolymers and less than 10% by weightother polymer compositions. The third layer has a first surface and asecond surface opposite the first surface. A third film ply isinterposed between the first film ply and the second film ply. The thirdfilm ply comprises a fourth layer formed of a polyolefin-based filmcontaining at least 90% by weight polyolefin homopolymers, copolymers,or terpolymers and less than 10% by weight other polymer compositions.The fourth layer has a first surface and a second surface opposite thefirst surface. A first adhesive layer is interposed between the firstfilm ply and the third film ply, the first adhesive layer laminating thefirst film ply to the third film ply, wherein the first surface of thefourth layer faces the second surface of the first layer. A secondadhesive layer is interposed between the third film ply and the secondfilm ply, the second adhesive layer laminating the third film ply to thesecond film ply, wherein the first surface of the third layer faces thesecond surface of the fourth layer. A printed layer is disposedintermediate the first layer and the third layer.

In more limited aspect, a melting temperature of the outermost surfaceof the laminated polyolefin-based film structure is at least 100 degreesCelsius higher than a melting temperature of the innermost surface ofthe laminated polyolefin-based film structure.

In another more limited aspect, a melting temperature of the outermostsurface of the laminated polyolefin-based film structure is at least 180degrees Celsius higher than a melting temperature of the innermostsurface of the laminated polyolefin-based film structure.

In another more limited aspect, the first layer, third layer, and fourthlayer are formed of a material selected from the group consisting ofpolyethylene-based films which contain at least 90% by weightpolyethylene homopolymers, copolymers, or terpolymers and less than 10%by weight other polymer compositions, polypropylene-based films whichcontains at least 90% by weight polypropylene homopolymers, copolymers,or terpolymers and less than 10% by weight other polymer compositions,and combinations thereof.

In another more limited aspect, the first layer is formed of apolyethylene-based film which contains at least 90% by weightpolyethylene homopolymers, copolymers, or terpolymers and less than 10%by weight other polymer compositions, the third layer is formed of apolyethylene-based film which contains at least 90% by weightpolyethylene homopolymers, copolymers, or terpolymers and less than 10%by weight other polymer compositions, and the fourth layer is formed ofa polyethylene-based polymer composition which contains at least 90% byweight polyethylene homopolymers, copolymers, or terpolymers and lessthan 10% by weight other polymer compositions.

In another more limited aspect, the first layer is formed of apolyethylene-based films which contain at least 95% by weightpolyethylene homopolymers, copolymers, or terpolymers and less than 5%by weight other polymer compositions, the third layer is formed of apolyethylene-based film which contains at least 95% by weightpolyethylene homopolymers, copolymers, or terpolymers and less than 5%by weight other polymer compositions, and the fourth layer is formed ofa polyethylene-based film which contains at least 95% by weightpolyethylene homopolymers, copolymers, or terpolymers and less than 5%by weight other polymer compositions.

In another more limited aspect, the printed layer comprises a reverseprinted ink layer disposed on the second surface of the first layer.

In another more limited aspect, the printed layer comprises a forwardprinted ink layer disposed on the first surface of the fourth layer.

In another more limited aspect, the printed layer comprises one of areverse printed ink layer disposed on the second surface of the fourthlayer and a forward printed ink layer disposed on the first surface ofthe third layer.

In another more limited aspect, the polyolefin-based film of the firstlayer, the polyolefin-based film of the third layer, and thepolyolefin-based film of the fourth layer are recyclablepolyolefin-based films.

In another more limited aspect, the laminated polyolefin-based filmstructure of further comprises a fourth film ply interposed between thethird film ply and the second film ply, the fourth film ply comprising afifth layer formed of a polyolefin-based film, the fifth layer having afirst surface and a second surface opposite the first surface. A thirdadhesive layer is interposed between the fourth film ply and the secondfilm ply, the third adhesive layer laminating the fourth film ply to thesecond film ply, wherein the first surface of the third layer faces thesecond surface of the fifth layer.

One advantage of the present development is that the laminatedpolyolefin-based film structures exhibit high heat resistance.

Another advantage of the present development resides in its utility inthe manufacture of film-based packaging. The presently disclosed filmstructure advantageously protects or maintains the integrity of theoverall film structure from warping, burning, premature melting, orproducing other aesthetically undesirable defects during the productfilling and distribution process. By reverse printing, or alternately byproviding a trapped forward printed ink layer, the inks are protectedfrom rubbing or being picked off when the package goes through abrasiveenvironments. The inks are also protected from the hot sealing barscommon on package filling lines.

Another advantage resides in its ability to provide a multi-webrecyclable polyolefin-based film package.

Still further advantages and benefits of the present invention willbecome apparent to those of ordinary skill in the art upon reading andunderstanding the following detailed description of the preferredembodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention may take form in various components and arrangements ofcomponents, and in various steps and arrangements of steps. Thedrawings, which are not to scale, are only for purposes of illustratingpreferred embodiments and are not to be construed as limiting theinvention.

FIG. 1 is a side cross sectional view of a first embodiment of alaminated film structure comprising two polyolefin-based films laminatedtogether.

FIG. 2 is a side cross sectional view of a second embodiment of alaminated film structure comprising two polyolefin-based films laminatedtogether.

FIG. 3 is a side cross sectional view of a first embodiment of alaminated film structure comprising three polyolefin-based filmslaminated together.

FIG. 4 is a side cross sectional view of a second embodiment of alaminated film structure comprising three polyolefin-based filmslaminated together.

FIG. 5 is a side cross sectional view of a third embodiment of alaminated film structure comprising three polyolefin-based filmslaminated together.

FIG. 6 is a side cross sectional view of a fourth embodiment of alaminated film structure comprising three polyolefin-based filmslaminated together.

FIG. 7 is a side cross-sectional view of a fifth embodiment of alaminated film structure comprising four or more polyolefin-based filmslaminated together.

FIG. 8 illustrates an exemplary polyolefin-based film.

FIGS. 9 and 10 illustrate exemplary multilayer polyolefin-based filmstructures.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Detailed embodiments of the present development are disclosed herein;however, it is to be understood that the disclosed embodiments aremerely exemplary of the invention, which may be embodied in variousforms. Therefore, specific structural and functional details disclosedherein are not to be interpreted as limiting but merely as a basis forthe claims and as a representative basis for teaching one skilled in theart to variously employ the present inventive concept in virtually anyappropriately detailed structure. Further, the terms and phrases usedherein are not intended to be limiting but rather to provide anunderstandable description of the present development.

The terms “a” or “an,” as used herein, are defined as one or more thanone. The term “another,” as used herein, is defined as at least a secondor more. The terms “including” and/or “having” as used herein, aredefined as comprising (i.e., open transition). The term “coupled” or“operatively coupled,” as used herein, is defined as indirectly ordirectly connected.

The present development relates to laminated polyolefin-based filmstructures comprising two or more polyolefin-based films laminatedtogether.

In certain embodiments, the present development relates to laminatedpolyethylene-based film structures comprising two or morepolyethylene-based films laminated together.

In certain embodiments, the present development relates to laminatedpolypropylene-based film structures comprising two or morepolypropylene-based films laminated together.

As used herein, the term “polyolefin-based film” refers to a film whichcontains at least 90% by weight polyolefin polymers and less than 10% byweight other polymer materials. The term “polyolefin polymer” includespolyolefin homopolymers, copolymers, terpolymers, or combinationsthereof. In certain more limited embodiments, the polyolefin-based filmsherein contain at least 95% by weight polyolefin polymers and less than5% by weight other polymer materials.

As used herein, the term “polyethylene-based film” refers to a filmwhich contains at least 90% by weight polyethylene polymers and lessthan 10% by weight other polymer materials. The term “polyethylenepolymer” includes polyethylene homopolymers, copolymers, terpolymers, orcombinations thereof. In certain more limited embodiments, thepolyethylene-based films herein contain at least 95% by weightpolyethylene-based polymers and less than 5% by weight other polymermaterials.

As used herein, the term “polypropylene-based film” refers to a filmwhich contains at least 90% by weight polypropylene polymers and lessthan 10% by weight other polymer materials. The term “polypropylenepolymer” includes polypropylene homopolymers, copolymers, terpolymers,or combinations thereof. In certain more limited embodiments, thepolypropylene-based films herein contain at least 95% by weightpolypropylene-based polymers and less than 5% by weight other polymermaterials.

Referring now to the drawings, FIGS. 1-7 illustrate exemplarypolyolefin-based packaging film structures manufactured in accordancewith exemplary embodiments of the present invention. The packaging filmstructures illustrated have enhanced heat resistance properties.

Referring now to FIG. 1 , there appears a first embodiment packagingfilm structure 10 which includes a first film ply 12 r laminated to asecond film ply 14. The first film ply 12 r is an outer film and thesecond film ply is an inner film. An adhesive layer 26 is interposedbetween the first film ply 12 r and the second film ply 14 to form alaminated structure. The adhesive layer 26 may be formed of any suitableadhesive, including single component adhesives, two component adhesives,solvent-based adhesives, solventless adhesives, water-based adhesives,acrylic adhesives, extruded polyethylene or polypropylene adhesivesystems, electron beam lamination adhesives, and UV laminationadhesives, as would be understood by persons skilled in the art.

The first film ply 12 r is formed on an outer portion of the packagingfilm structure 10. The film 12 r includes a polyolefin-based film 22,which may be a monolayer or multilayer structure. Exemplary polyolefinpolymers forming the polyolefin-based film 22 include, for example,homopolymers, copolymers, and terpolymers of ethylene, high densitypolyethylene (HDPE), medium density polyethylene (MDPE), linear mediumdensity polyethylene (LMDPE), low density polyethylene (LDPE), linearlow density polyethylene (LLDPE), very low density polyethylene (VLDPE),metallocene linear low-density polyethylene (mLLDPE), and homopolymers,copolymers, and terpolymers of polypropylene.

The first film ply 12 r further includes an energy-cured coating 18formed on a first surface of the polyolefin-based film 22 and forms anoutermost portion of the film structure 10. The energy-cured coating 18refers to a coating of one or more reactive monomer, oligomer, orpolymer compositions, which is irreversibly converted into a solidpolymer coating via reactive groups in the reactive monomer, oligomer,or polymer compositions upon the application of energy from a suitableenergy source, such as irradiation with electron beams or irradiationwith electromagnetic radiation, such as ultraviolet (UV) light orthermal radiation (heat).

In certain embodiments, the energy-cured coating 18 is applied over theentire first surface of the film 22. In certain embodiments, theenergy-cured coating 18 is applied over a portion of the entire firstsurface of the film 22. In certain embodiments, the energy-cured coating18 is applied as a continuous coating over the entire first surface ofthe film 22. In certain embodiments, the energy-cured coating 18 isapplied as a continuous coating over a portion of the first surface ofthe film 22. In certain embodiments, the energy-cured coating 18 isapplied as a discontinuous coating, e.g., as a pattern-applied coating,over the entire first surface of the film 22. In certain embodiments,the energy-cured coating 18 is applied as a discontinuous coating, e.g.,as a pattern-applied coating, over a portion of the first surface of thefilm 22. In certain embodiments wherein the energy-cured coating 18 isapplied only to a portion of the first surface of the film 22 and/or aspattern-applied coating, the film 22 may include registration indicia,fiducial markers, or the like to allow the film 22 to be registered toensure that the energy-cured coating 18 will be disposed at anappropriate on the film 22.

In preferred embodiments, the energy-cured coating 18 is a curedpolyacrylate composition formed from by curing a reactive polymercomposition comprising one or more monomers, oligomers, polymers,acrylates, polyacrylates, and/or polyacrylate copolymers. In certainembodiments, the energy-cured coating 18 is an electron beam curedcomposition that includes, but is not limited to, ethoxylatedtrimethylolpropane triacrylates, acrylated and acrylate ester resins,polyol acrylates, trimethylolpropane triacrylates, polydimethylsiloxaneacrylates, and maleic anhydrides. Other energy-cured coatingcompositions may include monomers and oligomers that contain vinyl andallyl compounds, as well as monomers and oligomers that are induced intoUV polymerization and curing through the mediation of photoinitiatorsand exposure to UV light and coatings that provide enhanced oxygen andmoisture barrier properties.

In certain embodiments, the energy-cured coating provides the outermostsurface of the film structure with a melting temperature which is atleast 100 degrees Celsius higher than the melting temperature of theinnermost surface of the film structure, wherein the “meltingtemperature” as used herein is the refers to the temperature at which bya heat seal formed a cohesive strength of at least one pound per inch ofseal width when subjecting the surfaces to a sealing pressure of 40pounds per square inch and a sealing dwell time of 0.5 seconds. Incertain embodiments, the energy-cured coating provides the outermostsurface of the film structure with a melting temperature which is atleast 120 degrees Celsius higher than the melting temperature of theinnermost surface of the film structure. In certain embodiments, theenergy-cured coating provides the outermost surface of the filmstructure with a melting temperature which is at least 160 degreesCelsius higher than the melting temperature of the innermost surface ofthe film structure. In certain embodiments, the energy-cured coatingprovides the outermost surface of the film structure with a meltingtemperature which is at least 180 degrees Celsius higher than themelting temperature of the innermost surface of the film structure.

In certain embodiments, the energy-cured coating 18 has a coatingthickness in the range of from about 0.78 micron (0.03 mil) to about 8microns (0.31 mil), preferably from about 2.3 microns (0.091 mil) toabout 4.7 micron (0.19 mil). In certain embodiments the energy-curedcoating 18 has a density in the range of from about 0.85 g/cc to about1.25 g/cc, preferably from about 1.02 to about 1.06 g/cc, and mostpreferably about 1.04 g/cc. In certain embodiments, the energy-curedcoating 18 has a coating weight in the range of from about 0.5 lb/ream(0.81 g/m²) to about 5.0 lb/ream (8.14 g/m²), preferably of from about1.5 lb/ream (2.44 g/m²) to about 3.0 lb/ream (4.88 g/m²).

A printing ink layer 24 r is disposed on a second, inward facing surfaceof the polyolefin-based film 22, the second surface opposite the firstsurface. The printing ink layer 24 r provides printed indicia intendedto appear on a packaging structure formed from the film structure 10.Because the printing ink layer 24 r is applied to the inward facingsurface of the polyolefin-based film 22, the printed material iseffected in a reverse printed format. The printing ink layer 24 r can beapplied to the second surface of the polyolefin-based film 22 via anyconventional printing method as would be understood by persons skilledin the art, including without limitation, using a rotogravure printingapparatus or flexographic printing apparatus.

The second film ply 14 includes a polyolefin-based film 28 formed on aninnermost portion of the film structure 10. The polyolefin-based film 28defines a sealant layer and may comprise any polyolefin polymer suitablefor providing a hermetic seal in a finished packaging article, andpreferably has a low seal initiation temperature/melting temperature.The polyolefin-based film 28 may be a monolayer or multilayer structure.Exemplary polyolefin polymers forming the polyolefin-based film 28include, for example, homopolymers, copolymers, and terpolymers ofethylene, high density polyethylene (HDPE), medium density polyethylene(MDPE), linear medium density polyethylene (LMDPE), low densitypolyethylene (LDPE), linear low density polyethylene (LLDPE), very lowdensity polyethylene (VLDPE), metallocene linear low-densitypolyethylene (mLLDPE), and homopolymers, copolymers, and terpolymers ofpolypropylene.

Referring now to FIG. 2 , there appears a second embodiment packagingfilm structure 20 which includes a first film ply 12 laminated to asecond film ply 14 f. The first film ply 12 is an outer film and thesecond film ply is an inner film. An adhesive layer 26 is interposedbetween the first film ply 12 and the second film ply 14 f to form alaminated structure. The adhesive layer 26 may be formed of an adhesivematerial as described above by way of reference to FIG. 1 .

The first film ply 12 is formed on an outer portion of the packagingfilm structure 20. The first film ply 12 includes a polyolefin-basedfilm 22, which may be a monolayer or multilayer structure and may beformed of a polyolefin-based film as described above by way of referenceto FIG. 1 .

The first film ply 12 further includes an energy-cured coating 18 formedon a first surface of the polyolefin-based film 22 and forms anoutermost portion of the film structure 20. The energy-cured coating 18may be formed of a material and applied as described above by way ofreference to FIG. 1 . In preferred embodiments, the energy-cured coating18 is a cured polyacrylate composition formed from by curing a reactivepolymer composition comprising one or more polyacrylates and/orpolyacrylate copolymers. In certain embodiments, the energy-curedcoating 18 is an electron beam cured polyacrylate composition.

The second film ply 14 f includes a polyolefin-based film 28 and isformed on an innermost portion of the film structure 20. Thepolyolefin-based film 28 defines a sealant layer and may comprise anypolyolefin polymer suitable for providing a hermetic seal in a finishedpackaging article, and preferably has a low seal initiationtemperature/melting temperature. The polyolefin-based film 28, which maybe a monolayer or multilayer structure, may comprise a polyolefinpolymer material as described above by way of reference to FIG. 1 . Incertain embodiments, the polyolefin-based film 28 is formed of lowdensity polyethylene (LDPE) or linear low density polyethylene (LLDPE).

The second film ply 14 f further includes a printing ink layer 24 fdisposed on a first, outward facing surface of the polyolefin-based film22. The printing ink layer 24 f provides printed indicia intended toappear on a packaging structure formed from the film structure 20.Because the printing ink layer 24 f is applied to the outward facingsurface of the polyolefin-based film 22, the printed material iseffected in a front printed format. The printing ink layer 24 f can beapplied to the first surface of the polyolefin-based film 22 via anyconventional printing method as would be understood by persons skilledin the art, including without limitation, using a rotogravure printingapparatus or flexographic printing apparatus.

Referring now to FIG. 3 , there appears a third embodiment packagingfilm structure 30, comprising a first film ply 12 r, a third film ply16, and a second film ply 14, which are laminated together. The firstfilm ply 12 r is an outer film, the second film ply is an inner film,and the third film ply is an intermediate film. A first adhesive layer26 a is interposed between the first film ply 12 r and the third filmply 16 and a second adhesive layer 26 b is interposed between the thirdfilm ply 16 and the second film ply 14, to form a laminated structure.The adhesive layers 26 a and 26 b may be formed of an adhesive materialas described above by way of reference to FIG. 1 .

The first film ply 12 r is formed on an outer portion of the packagingfilm structure 30. The film 12 r includes a polyolefin-based film 22,which may be a monolayer or structure, and may comprise a polyolefinpolymer material as described above by way of reference to FIG. 1 .

The first film ply 12 r further includes an energy-cured coating 18formed on a first surface of the polyolefin-based film 22 and forms anoutermost portion of the film structure 30. The energy-cured coating 18may be formed of a material and applied as described above by way ofreference to FIG. 1 . In preferred embodiments, the energy-cured coating18 is a cured polyacrylate composition formed from by curing a reactivepolymer composition comprising one or more polyacrylates and/orpolyacrylate copolymers. In certain embodiments, the energy-curedcoating 18 is an electron beam cured polyacrylate composition.

A printing ink layer 24 r is disposed on a second, inward facing surfaceof the polyolefin-based film 22, opposite the first surface. Theprinting ink layer 24 r provides printed indicia intended to appear on apackaging structure formed from the film structure 30. Because theprinting ink layer 24 r is applied to the inward facing surface of thepolyolefin-based film 22, the printed material is effected in a reverseprinted format. The printing ink layer 24 r can be applied to the secondsurface of the polyolefin-based film 22 via any conventional printingmethod as would be understood by persons skilled in the art, includingwithout limitation, using a rotogravure printing apparatus orflexographic printing apparatus.

The second film ply 14 includes a polyolefin-based film 28 and is formedon an innermost portion of the film structure 30. The polyolefin-basedfilm 28 defines a sealant layer and may comprise any polyolefin polymersuitable for providing a hermetic seal in a finished packaging article,and preferably has a low seal initiation temperature/meltingtemperature. The polyolefin-based film 28, which may be a monolayer ormultilayer structure, may comprise a polyolefin polymer material asdescribed above by way of reference to FIG. 1 . In certain embodiments,the polyolefin-based film 28 is formed of low density polyethylene(LDPE) or linear low density polyethylene (LLDPE).

The third film ply 16 is interposed between the first film ply 12 r andthe second film ply 14. The third film ply 16 includes apolyolefin-based film 32, which may be a monolayer or multilayerstructure. The polyolefin-based film 32 may be a monolayer or multilayerstructure. Exemplary polyolefin polymers for forming thepolyolefin-based film 32 include, for example, homopolymers, copolymers,and terpolymers of ethylene, high density polyethylene (HDPE), mediumdensity polyethylene (MDPE), linear medium density polyethylene (LMDPE),low density polyethylene (LDPE), linear low density polyethylene(LLDPE), very low density polyethylene (VLDPE), metallocene linearlow-density polyethylene (mLLDPE), and homopolymers, copolymers, andterpolymers of polypropylene.

Referring now to FIG. 4 , there appears a fourth embodiment packagingfilm structure 40, comprising a first film ply 12, a third film ply 16f, and a second film ply 14, which are laminated together. The firstfilm ply 12 is an outer film, the second film ply is an inner film, andthe third film ply is an intermediate film. A first adhesive layer 26 ais interposed between the first film ply 12 and the third film ply 16 fand a second adhesive layer 26 b is interposed between the third filmply 16 f and the second film ply 14, to form a laminated structure. Theadhesive layers 26 a and 26 b may be formed of an adhesive material asdescribed above by way of reference to FIG. 1 .

The first film ply 12 is formed on an outer portion of the packagingfilm structure 40. The film 12 includes a polyolefin-based film 22,which may be a monolayer or multilayer structure and which may comprisea polyolefin polymer as described above by way of reference to FIG. 1 .

The first film ply 12 further includes an energy-cured coating 18 formedon a first surface of the polyolefin-based film 22 and forms anoutermost portion of the film structure 40. The energy-cured coating 18may be formed of a material and applied as described above by way ofreference to FIG. 1 . In preferred embodiments, the energy-cured coating18 is a cured polyacrylate composition formed from by curing a reactivepolymer composition comprising one or more polyacrylates and/orpolyacrylate copolymers. In certain embodiments, the energy-curedcoating 18 is an electron beam cured polyacrylate composition.

The second film ply 14 includes a polyolefin-based film 28 and is formedon an innermost portion of the film structure 40. The polyolefin-basedfilm 28 defines a sealant layer and may comprise any polyolefin polymersuitable for providing a hermetic seal in a finished packaging article,and preferably has a low seal initiation temperature/meltingtemperature. The polyolefin-based film 28, which may be a monolayer ormultilayer structure, may be formed of a polyolefin polymer material asdescribed above by way of reference to FIG. 1 . In certain embodiments,the polyolefin-based film 28 is formed of low density polyethylene(LDPE) or linear low density polyethylene (LLDPE).

The third film ply 16 f is interposed between the first film ply 12 andthe second film ply 14. The third film ply 16 f includes apolyolefin-based film 32, which may be a monolayer or multilayerstructure. The polyolefin-based film 32 may comprise a polyolefinpolymer material as described above by way of reference to FIG. 3 .

The third film ply 16 f further includes a printing ink layer 24 fdisposed on a first, outward facing surface of the polyolefin-based film32. The printing ink layer 24 f provides printed indicia intended toappear on a packaging structure formed from the film structure 40.Because the printing ink layer 24 f is applied to the outward facingsurface of the polyolefin-based film 32, the printed material iseffected in a front printed format. The printing ink layer 24 f can beapplied to the first surface of the polyolefin-based film 32 via anyconventional printing method as would be understood by persons skilledin the art, including without limitation, using a rotogravure printingapparatus or flexographic printing apparatus.

Referring now to FIG. 5 , there appears a fifth embodiment packagingfilm structure 50 comprising a first film ply 12, a third film ply 16 r,and a second film ply 14, which are laminated together. The first filmply 12 is an outer film, the second film ply is an inner film, and thethird film ply is an intermediate film. A first adhesive layer 26 a isinterposed between the first film ply 12 and the third film ply 16 r anda second adhesive layer 26 b is interposed between the third film ply 16r and the second film ply 14, to form a laminated structure. Theadhesive layers 26 a and 26 b may be formed of an adhesive material asdescribed above by way of reference to FIG. 1 .

The first film ply 12 is formed on an outer portion of the packagingfilm structure 50. The film 12 includes a polyolefin-based film 22,which may be a monolayer or multilayer structure, and may comprise of apolyolefin polymer material as described above by way of reference toFIG. 1 .

The first film ply 12 further includes an energy-cured coating 18 formedon a first surface of the polyolefin-based film 22 and forms anoutermost portion of the film structure 50. The energy-cured coating 18may be formed of a material and applied as described above by way ofreference to FIG. 1 . In preferred embodiments, the energy-cured coating18 is a cured polyacrylate composition formed from by curing a reactivepolymer composition comprising one or more polyacrylates and/orpolyacrylate copolymers. In certain embodiments, the energy-curedcoating 18 is an electron beam cured polyacrylate composition.

The second film ply 14 includes a polyolefin-based film 28 and is formedon an innermost portion of the film structure 50. The polyolefin-basedfilm 28 defines a sealant layer and comprise any polyolefin polymersuitable for providing a hermetic seal in a finished packaging article,and preferably has a low seal initiation temperature/meltingtemperature. The polyolefin-based film 28, which may be a monolayer ormultilayer structure, may be formed of a polyolefin polymer material asdescribed above by way of reference to FIG. 1 . In certain embodiments,the polyolefin-based film 28 is formed of low density polyethylene(LDPE) or linear low density polyethylene (LLDPE).

The third film ply 16 r is interposed between the first film ply 12 andthe second film ply 14. The third film ply 16 r includes apolyolefin-based film 32, which may be a monolayer or multilayerstructure. The polyolefin-based film 32 may comprise a polyolefinpolymer material as described above by way of reference to FIG. 3 .

The third film ply 16 r further includes a printing ink layer 24 rdisposed on an inward facing surface of the polyolefin-based film 32.The printing ink layer 24 r provides printed indicia intended to appearon a packaging structure formed from the film structure 50. Because theprinting ink layer 24 r is applied to the inward facing surface of thepolyolefin-based film 32, the printed material is effected in a reverseprinted format. The printing ink layer 24 r can be applied to the inwardfacing surface of the polyolefin-based film 32 via any conventionalprinting method as would be understood by persons skilled in the art,including without limitation, using a rotogravure printing apparatus orflexographic printing apparatus.

Referring now to FIG. 6 , there appears a sixth embodiment packagingfilm structure 60, comprising a first film ply 12, a third film ply 16,and a second film ply 14 f, which are laminated together. The first filmply 12 is an outer film, the second film ply is an inner film, and thethird film ply is an intermediate film. A first adhesive layer 26 a isinterposed between the first film ply 12 and the third film ply 16 and asecond adhesive layer 26 b is interposed between the third film ply 16and the second film ply 14 f, to form a laminated structure. Theadhesive layers 26 a and 26 b may be formed of an adhesive material asdescribed above by way of reference to FIG. 1 .

The first film ply 12 is formed on an outer portion of the packagingfilm structure 60. The film 12 includes a polyolefin-based film 22,which may be a monolayer or multilayer structure, and may be formed of apolyolefin polymer material as described above by way of reference toFIG. 1 .

The first film ply 12 further includes an energy-cured coating 18 formedon a first surface of the polyolefin-based film 22 and forms anoutermost portion of the film structure 60. The energy-cured coating 18may be formed of a material and applied as described above by way ofreference to FIG. 1 . In preferred embodiments, the energy-cured coating18 is a cured polyacrylate composition formed from by curing a reactivepolymer composition comprising one or more polyacrylates and/orpolyacrylate copolymers. In certain embodiments, the energy-curedcoating 18 is an electron beam cured polyacrylate composition.

The second film ply 14 f includes a polyolefin-based film 28 and isformed on an innermost portion of the film structure 60. Thepolyolefin-based film 28 defines a sealant layer and may comprise anypolyolefin polymer suitable for providing a hermetic seal in a finishedpackaging article, and preferably has a low seal initiationtemperature/melting temperature. The polyolefin-based film 28, which maybe a monolayer or multilayer structure, may be formed of a polyolefinpolymer material as described above by way of reference to FIG. 1 . Incertain embodiments, the polyolefin-based film 28 is formed of lowdensity polyethylene (LDPE) or linear low density polyethylene (LLDPE).

The third film ply 16 is interposed between the first film ply 12 andthe second film ply 14 f. The third film ply 16 includes apolyolefin-based film 32, which may be a monolayer or multilayerstructure. The polyolefin-based film 32 may comprise a polyolefinpolymer material as described above by way of reference to FIG. 3 .

A printing ink layer 24 f is disposed on an outward facing surface ofthe polyolefin-based film 32, opposite the innermost surface. Theprinting ink layer 24 f provides printed indicia intended to appear on apackaging structure formed from the film structure 60. Because theprinting ink layer 24 f is applied to the outward facing surface of thepolyolefin-based film 32, the printed material is effected in a frontprinted format. The printing ink layer 24 f can be applied to theoutward facing surface of the polyolefin-based film 32 via anyconventional printing method as would be understood by persons skilledin the art, including without limitation, using a rotogravure printingapparatus or flexographic printing apparatus.

Referring now to FIG. 7 , there appears a sixth embodiment packagingfilm structure 70, comprising a first film ply 12, a third film ply 16,a second film ply 14, and one or more (up to “X”) film plies 4 throughN, designated 16 a, where X is 1, 2, 3, 4, 5, 6, 7, 8, 9, or more, and Nis 4, 5, 6, 7, 8, 9, 10, 11, 12, or more, which are laminated together.The first film ply 12 is an outer film, the second film ply is an innerfilm, and the third film ply is an intermediate film. A first adhesivelayer 26 a is interposed between the first film ply 12 and the thirdfilm ply 16 and a second adhesive layer 26 b is interposed between thethird film ply 16 and the fourth film ply 16 a, and further adhesivelayers 26 c are disposed between the fourth and subsequent film plies 16a and the second film ply 14 to form a laminated structure. The adhesivelayers 26 a, 26 b, and 26 c may be formed of an adhesive material asdescribed above by way of reference to FIG. 1 .

The first film ply 12 is formed on an outer portion of the packagingfilm structure 70. The film 12 includes a polyolefin-based film 22,which may be a monolayer or multilayer structure, and may comprise apolyolefin polymer material as described above by way of reference toFIG. 1 .

The first film ply 12 further includes an energy-cured coating 18 formedon a first surface of the polyolefin-based film 22 and forms anoutermost portion of the film structure 70. The energy-cured coating 18may be formed of a material and applied as described above by way ofreference to FIG. 1 . In preferred embodiments, the energy-cured coating18 is a cured polyacrylate composition formed from by curing a reactivepolymer composition comprising one or more polyacrylates and/orpolyacrylate copolymers. In certain embodiments, the energy-curedcoating 18 is an electron beam cured polyacrylate composition.

The second film ply 14 includes a polyolefin-based film 28 and is formedon an innermost portion of the film structure 70. The polyolefin-basedfilm 28 defines a sealant layer and may be any polyolefin polymersuitable for providing a hermetic seal in a finished packaging article,and preferably has a low seal initiation temperature/meltingtemperature. The polyolefin-based film 28, which may be a monolayer ormultilayer structure, may be formed of a polyolefin polymer material asdescribed above by way of reference to FIG. 1 . In certain embodiments,the polyolefin-based film 28 is formed of low density polyethylene(LDPE) or linear low density polyethylene (LLDPE).

The third film ply 16 is interposed between the first film ply 12 andthe one or more film plies 16 a. The third film ply 16 includes apolyolefin-based film 32, which may be a monolayer or multilayerstructure. The polyolefin-based film 32 may comprise a polyolefinpolymer material as described above by way of reference to FIG. 3 .

The film plie(s) 4 through N 16 a are interposed between the third filmply 16 and the second film ply layer 14. The fourth film ply layer(s) 16a include a polyolefin-based film 32 a, which may be a monolayer ormultilayer structure. The polyolefin-based film 32 a may be formed of apolyolefin polymer material as described above by way of reference toFIG. 3 .

A printing ink layer 24 f or 24 r is disposed on an outward or inwardfacing surface, respectively, of a selected one of the polyolefin-basedfilms 32, 32 a, or alternatively, on the inward facing surface of thepolyolefin layer 22 or the outward facing surface of the polyolefinlayer 28. The printing ink layer 24 f, 24 r provides printed indiciaintended to appear on a packaging structure formed from the filmstructure 70. The printed material comprising the printing ink layer iseffected in a front printed format (24 f) or a reverse printed format(24 r), depending on whether the printing layer is applied to an outwardfacing surface or an inward facing surface. The printing ink layer 24 f,24 r can be applied via any conventional printing method as would beunderstood by persons skilled in the art, including without limitation,using a rotogravure printing apparatus or flexographic printingapparatus.

One method of manufacturing a laminated film structure comprises thesteps of applying a set of printing inks to one side of a recyclablepolyolefin-based film web and applying an energy-cured coating to theother side of that same web to form a first film ply. The first film plyis then laminated to a second film ply comprising a recyclablepolyolefin-based film web, such that the inks are sandwiched between thewebs. In certain embodiments, the steps are performed in a continuousprocess step. Alternatively, the steps can be performed in as separateprocess steps.

Another method of manufacturing a laminated film structure comprisesapplying an energy-cured coating to the outer side of a firstpolyolefin-based film to form a first film ply. Printing inks areapplied to the surface of a second polyolefin-based film to form asecond film ply. The first and second film plies are then laminatedtogether with an adhesive such that the printing ink layer is disposedon an interior surface of the laminate.

Yet another method of manufacturing a laminated film structure comprisesapplying an energy-cured coating to the outermost side of apolyolefin-based film to form an outer film ply. An intermediate filmply comprising a polyolefin-based film and an inner film ply comprisinga polyolefin-based film are also provided. The innermost side of theinner film ply defines a sealant layer. A printing ink layer is appliedto any one of the inward facing surface of outer film ply, either sideof the intermediate film ply, or the outward facing surface of the innerfilm ply. The outer, intermediate, and inner film plies are thenlaminated together, with the intermediate film ply interposed betweenthe outer and inner film plies. This also provides a printed ink layersandwiched within layers while having the energy-cured coating on theoutermost side of the film structure.

The present development was reduced to practice and the heat resistancewas compared to recyclable polyolefin-based film having no coating or atraditional wet coating cured through ambient or heat airflow. The filmstructures were tested using a sealing pressure of 40 psi and a sealingdwell time of 0.5 seconds. The sealing temperature ranged from 60degrees C. to 260 degrees C. Data showing the improved heat resistanceof an energy-cured coating on a 2-ply recyclable polyethylene-based filmstructure in accordance with the present disclosure versus 2-ply filmstructures with no coating or a traditional wet coating cured throughambient or heat airflow are shown in Table 1.

TABLE 1 Film Heat Resistance Test Results Conditions: Heat Seal @ 40psi, 0.5 sec-(seal strength (g/in)) Recyclable Recyclable Recyclable Lam2-Ply Lam 2-Ply Lam 2-Ply 90 ga PE/3 mil PE Temp 100 ga PE/3 mil PE 90ga PE/3 mil PE Energy-Cured (° C.) Wet Coating No Coating Coating  60Inner surface Inner surface Inner surface not melted not melted notmelted Outer surface Outer surface Outer surface not melted not meltednot melted  80 Inner surface Inner surface Inner surface initial meltinitial melt initial melt Outer surface Outer surface Outer surface notmelted not melted not melted 130 Inner surface melted Inner surfacemelted Inner surface melted Outer surface Outer surface Outer surfacenot melted not melted not melted 135 Inner surface melted Inner surfacemelted Inner surface melted Outer surface Outer surface Outer surfacestarting to shrink not melted not melted 140 Inner surface melted Innersurface melted Inner surface melted Outer melt shrink Outer melted/stickOuter surface 3 mm in MD/TD to top metal jaw not melted 150 Innersurface melted Outer surface not melted 200 Inner surface melted Outersurface not melted 230 Inner surface melted Outer surface not melted 260Inner surface melted Outer surface not melted

As can be seen from the data in Table 1, the film structure having theenergy-cured coating in accordance with the present development wasfound to have a temperature differential between inner layer melting andouter layer melting of at least 180 degrees C.; whereas, the filmstructures without no coating or a traditional dried wet coating had atemperature differential between inner layer melting and outer layermelting of at most 60 degrees C.

As mentioned above, each of the recyclable polyolefin layers 22, 28, and32, which may be the same or different, may comprise monolayer ormultilayer structures. The recyclable polyolefin layers 22, 28, and 32may be coextrusions, extrusion laminations, laminations, or combinationsthereof. In certain embodiments, one or more of the recyclablepolyolefin layers 22, 28, and 32 includes a barrier layer for preventingor reducing the transmission of oxygen or other gas molecules ormoisture vapor through the film structure. FIGS. 8 and 9 illustrateexemplary polyolefin-based films 22, 28, and 32. FIG. 8 illustrates apolyolefin-based film comprising a polyolefin polymer layer 44, which isoperable to embody the polyolefin-based film layers 22, 28, or 32. FIG.9 illustrates a five-layer polyethylene-based film structure comprisinga barrier layer 40 disposed between two polyolefin layers 44. Tie layers42 are disposed intermediate the barrier layer 40 and each of thepolyolefin layers 44. Exemplary tie layers include maleic anhydride(MAH) or other tie resin or adhesion promotor as would be known bypersons skilled in the art. Although a 5-layer multilayer film structureis illustrated, it will be recognized that other numbers of layers,including 7 layer, 9-layer, and others are also contemplated. Exemplarybarrier layers 40 include polymer barrier layers such as ethylene-vinylalcohol (EVOH), polyvinyl alcohol (PVOH), polyamides, e.g., polyamidenylon (PA) (e.g., polyamide nylon 6 (PA6)), with or withoutcompatibilizer additives.

Referring now to FIG. 10 , in still further embodiments, each of thepolyolefin-based film layers 22, 28, and 32, may comprise a monolayer ormultilayer polyolefin polymer structure 44 having an organic orinorganic barrier layer 46. Exemplary barrier layers 46 include but arenot limited to metal oxide coated films such as aluminum oxide (AlOx),silicon oxide (SiOx), or combinations thereof, coated film layers, andmetalized film, e.g., aluminum coated film.

The invention has been described with reference to the preferredembodiment. Modifications and alterations will occur to others upon areading and understanding of the preceding detailed description. It isintended that the invention be construed as including all suchmodifications and alterations insofar as they come within the scope ofthe appended claims or the equivalents thereof.

What is claimed is:
 1. A laminated polyolefin-based film structurecomprising: a first film ply comprising: a first layer formed of apolyolefin-based film containing at least 90% by weight polyolefinhomopolymers, copolymers, or terpolymers and less than 10% by weightother polymer compositions, the first layer having a first surface and asecond surface opposite the first surface; and a second layer disposedon the first surface of the first layer, the second layer comprising anenergy-cured coating and defining an outermost surface of the laminatedpolyolefin-based film structure; and a second film ply comprising: athird layer formed of a polyolefin-based film containing at least 90% byweight polyolefin homopolymers, copolymers, or terpolymers and less than10% by weight other polymer compositions, the third layer having a firstsurface and a second surface opposite the first surface, the secondsurface of the third layer defining an innermost surface of thelaminated polyolefin-based film structure; an adhesive layer interposedbetween the first film ply and the second film ply, the adhesive layerlaminating the first film ply to the second film ply, wherein the firstsurface of the third layer faces the second surface of the first layer;and a printed layer disposed intermediate the first layer and the thirdlayer.
 2. The laminated polyolefin-based film structure of claim 1,wherein a melting temperature of the outermost surface of the laminatedpolyolefin-based film structure is at least 100 degrees Celsius higherthan a melting temperature of the innermost surface of the laminatedpolyolefin-based film structure.
 3. The laminated polyolefin-based filmstructure of claim 1, wherein a melting temperature of the outermostsurface of the laminated polyolefin-based film structure is at least 180degrees Celsius higher than a melting temperature of the innermostsurface of the laminated polyolefin-based film structure.
 4. Thelaminated polyolefin-based film structure of claim 1, wherein the firstlayer and third layer are formed of a material selected from the groupconsisting of polyethylene-based films which contain at least 90% byweight polyethylene homopolymers, copolymers, or terpolymers and lessthan 10% by weight other polymer compositions, polypropylene-based filmswhich contains at least 90% by weight polypropylene homopolymers,copolymers, or terpolymers and less than 10% by weight other polymercompositions, and combinations thereof.
 5. The laminatedpolyolefin-based film structure of claim 1, wherein the first layer isformed of a polyethylene-based film which contains at least 90% byweight polyethylene homopolymers, copolymers, or terpolymers and lessthan 10% by weight other polymer compositions and the third layer isformed of a polyethylene-based film which contains at least 90% byweight polyethylene homopolymers, copolymers, or terpolymers and lessthan 10% by weight other polymer compositions.
 6. The laminatedpolyolefin-based film structure of claim 5, wherein the first layer isformed of a polyethylene-based films which contain at least 95% byweight polyethylene homopolymers, copolymers, or terpolymers and lessthan 5% by weight other polymer compositions and the third layer isformed of a polyethylene-based film which contains at least 95% byweight polyethylene homopolymers, copolymers, or terpolymers and lessthan 5% by weight other polymer compositions.
 7. The laminatedpolyolefin-based film structure of claim 1, wherein the printed layercomprises a reverse printed ink layer disposed on the second surface ofthe first layer.
 8. The laminated polyolefin-based film structure ofclaim 1, wherein the printed layer comprises a forward printed ink layerdisposed on the first surface of the third layer.
 9. The laminatedpolyolefin-based film structure of claim 1, wherein the polyolefin-basedfilm of the first layer and the polyolefin-based film of the third layercomprise recyclable polyolefin polymers.
 10. A laminatedpolyolefin-based film structure comprising: a first film ply comprising:a first layer formed of a polyolefin-based film containing at least 90%by weight polyolefin homopolymers, copolymers, or terpolymers and lessthan 10% by weight other polymer compositions, the first layer having afirst surface and a second surface opposite the first surface; and asecond layer disposed on the first surface of the first layer, thesecond layer comprising an energy-cured coating; and a second film plycomprising: a third layer formed of a polyolefin-based film containingat least 90% by weight polyolefin homopolymers, copolymers, orterpolymers and less than 10% by weight other polymer compositions, thethird layer having a first surface and a second surface opposite thefirst surface; a third film ply interposed between the first film plyand the second film ply, the third film ply comprising: a fourth layerformed of a polyolefin-based film containing at least 90% by weightpolyolefin homopolymers, copolymers, or terpolymers and less than 10% byweight other polymer compositions, the fourth layer having a firstsurface and a second surface opposite the first surface; a firstadhesive layer interposed between the first film ply and the third filmply, the first adhesive layer laminating the first film ply to the thirdfilm ply, wherein the first surface of the fourth layer faces the secondsurface of the first layer; a second adhesive layer interposed betweenthe third film ply and the second film ply, the second adhesive layerlaminating the third film ply to the second film ply, wherein the firstsurface of the third layer faces the second surface of the fourth layer;and a printed layer disposed intermediate the first layer and the thirdlayer.
 11. The laminated polyolefin-based film structure of claim 10,wherein a melting temperature of the outermost surface of the laminatedpolyolefin-based film structure is at least 100 degrees Celsius higherthan a melting temperature of the innermost surface of the laminatedpolyolefin-based film structure.
 12. The laminated polyolefin-based filmstructure of claim 10, wherein a melting temperature of the outermostsurface of the laminated polyolefin-based film structure is at least 180degrees Celsius higher than a melting temperature of the innermostsurface of the laminated polyolefin-based film structure.
 13. Thelaminated polyolefin-based film structure of claim 10, wherein the firstlayer, third layer, and fourth layer are formed of a material selectedfrom the group consisting of polyethylene-based films which contain atleast 90% by weight polyethylene homopolymers, copolymers, orterpolymers and less than 10% by weight other polymer compositions,polypropylene-based films which contains at least 90% by weightpolypropylene homopolymers, copolymers, or terpolymers and less than 10%by weight other polymer compositions, and combinations thereof.
 14. Thelaminated polyolefin-based film structure of claim 10, wherein the firstlayer is formed of a polyethylene-based film which contains at least 90%by weight polyethylene homopolymers, copolymers, or terpolymers and lessthan 10% by weight other polymer compositions, the third layer is formedof a polyethylene-based film which contains at least 90% by weightpolyethylene homopolymers, copolymers, or terpolymers and less than 10%by weight other polymer compositions, and the fourth layer is formed ofa polyethylene-based polymer composition which contains at least 90% byweight polyethylene homopolymers, copolymers, or terpolymers and lessthan 10% by weight other polymer compositions.
 15. The laminatedpolyolefin-based film structure of claim 14, wherein the first layer isformed of a polyethylene-based films which contain at least 95% byweight polyethylene homopolymers, copolymers, or terpolymers and lessthan 5% by weight other polymer compositions, the third layer is formedof a polyethylene-based film which contains at least 95% by weightpolyethylene homopolymers, copolymers, or terpolymers and less than 5%by weight other polymer compositions, and the fourth layer is formed ofa polyethylene-based film which contains at least 95% by weightpolyethylene homopolymers, copolymers, or terpolymers and less than 5%by weight other polymer compositions.
 16. The laminated polyolefin-basedfilm structure of claim 10, wherein the printed layer comprises areverse printed ink layer disposed on the second surface of the firstlayer.
 17. The laminated polyolefin-based film structure of claim 10,wherein the printed layer comprises a forward printed ink layer disposedon the first surface of the fourth layer.
 18. The laminatedpolyolefin-based film structure of claim 10, wherein the printed layercomprises one of: a reverse printed ink layer disposed on the secondsurface of the fourth layer; and a forward printed ink layer disposed onthe first surface of the third layer.
 19. The laminated polyolefin-basedfilm structure of claim 10, wherein the polyolefin-based film of thefirst layer, the polyolefin-based film of the third layer, and thepolyolefin-based film of the fourth layer are recyclablepolyolefin-based films.
 20. The laminated polyolefin-based filmstructure of claim 10, further comprising: a fourth film ply interposedbetween the third film ply and the second film ply, the fourth film plycomprising a fifth layer formed of a polyolefin-based film, the fifthlayer having a first surface and a second surface opposite the firstsurface; and a third adhesive layer interposed between the fourth filmply and the second film ply, the third adhesive layer laminating thefourth film ply to the second film ply, wherein the first surface of thethird layer faces the second surface of the fifth layer.